<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>3-react生命周期(新)</title>
</head>

<body>
    <!-- 准备好一个容器 -->
    <div id="test"></div>
    <!-- 引入react核心库 -->
    <script type="text/javascript" src="../js/17.0.1/react.development.js"></script>
    <!-- 引入react-dom，用于支持react操作DOM -->
    <script type="text/javascript" src="../js/17.0.1/react-dom.development.js"></script>
    <!-- 引入babel，用于将jsx转换为js -->
    <script type="text/javascript" src="../js/17.0.1/babel.min.js"></script>

    <script type="text/babel">  //此处一定要写babel

        //创建组件
        class Count extends React.Component {

            //构造器
            constructor(props) {
                console.log('Count----constructor');
                super(props);
                //初始化状态
                this.state = { count: 0 }
            }

            //加1按钮的回调
            add = () => {
                //获取原状态
                const { count } = this.state
                //更新状态
                this.setState({ count: count + 1 })
            }

            //卸载组件按钮的回调
            death = () => {
                ReactDOM.unmountComponentAtNode(document.querySelector('#test'));
            }


            //强制更新组件按钮的回调
            force = () => {
                this.forceUpdate();
            }

            //组件将要挂载的钩子
            UNSAFE_componentWillMount() {
                console.log('Count----componentWillMount')
            }

            //组件挂载完毕的钩子
            componentDidMount() {
                console.log('Count----componentDidMount')
            }

            //组件将要卸载的钩子
            componentWillUnmount() {
                console.log('Count----componentWillUnmount')
            }

            //控制组件更新的“阀门”
            shouldComponentUpdate() {
                console.log('Count----shouldComponentUpdate')
                return true
            }


            //组件将要更新的钩子
            UNSAFE_componentWillUpdate() {
                console.log('Count----componentWillUpdate')

            }

            //组件更新完成的钩子
            componentDidUpdate() {
                console.log('Count----componentDidUpdate')
            }

            render() {
                console.log('Count-----render')
                const { count } = this.state;
                return (
                    <div>
                        <h2>当前求和为:{count}</h2>
                        <button onClick={this.add}>点我+1</button>
                        <button onClick={this.death}>卸载组件</button>
                        <button onClick={this.force}>不更改任何状态中的数据，强制更新一下</button>
                    </div>
                )
            }
        }

        //父组件A
        class A extends React.Component {
            //初始化状态
            state = { carName: '奔驰' }

            changeCar = () => {
                this.setState({ carName: '奥拓' })
            }
            render() {
                return (
                    <div>
                        <div>我是A组件</div>
                        <button onClick={this.changeCar}>换车</button>
                        <B carName={this.state.carName} />
                    </div>

                )
            }
        }

        //子组件B
        class B extends React.Component {

            //组件将要接收新的props的钩子
            UNSAFE_componentWillReceiveProps(props) {
                console.log('B----componentWillReceiveProps', props)
            }
            render() {
                console.log('B----render')
                return (
                    <div>我是B组件，接收到的成是:{this.props.carName}</div>
                )
            }
        }

        //渲染组件
        ReactDOM.render(<Count />, document.querySelector('#test'));
        // ReactDOM.render(<A />, document.querySelector('#test'));
    </script>
</body>

</html>